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In the cycle, blue helps Spirits, black helps Rogues, red helps Goblins, and green helps Cats
It also stops graveyard decks from looping or playing Living Death, which can be a lose-condition for Voltron builds
To cover the three things I expect to hear the most in advance: I know we didn't include The Cool S
The Path to the Peak decks, and the Counter Toolbox decks
Hushbringer can stop everything from Dockside Extortionist to Blood Artist , so it might be worth running fewer of your own enters-the-battlefield creatures to deter certain powerful cards